I began blogging with $100 Dialysis – the vision. The technical challenge is to develop cheap and perhaps novel means to filter the blood of nitrogenous waste products. Below is an example of three approaches, one is a more user-friendly way to use existing technology, another utilizes nanotech, and the third although not aimed at dialysis is an example of new thinking.
Peritoneal dialysis is a form of dialysis whereby the abdomen lining (called the peritoneum) within the body is used to filter the blood. Simply, the dialysis fluid is pumped into the cavity formed by this natural filter. Once it has absorbed some of the waste from the blood filtered through the peritoneum it is pumped back out again. Not everyone is eligible for periotoneal dialysis, but for those who are the concept of a portable dialysis is very welcome. Progress is definitely being made, have a look here.
Also developing wearable dialysis, but this time using an external device to remove the waste is the Dutch company Nanodialysis. Rather than simply filter the unwanted particles through small pores they get them to adhere to a surface, a process called adsorption. From there they get them to decompose to nitrogen, hydrogen, and carbon dioxide. The company claims that not only will this be cheaper (yeah) and more convenient it will also increase life expectancy 10 to 15 years over standard hemodialysis! This is quite an incredible claim and as they are yet to complete animal trials is premature. Nevertheless, it is definitely a space worth watching.
Some clever people in MIT and the National University of Singapore have demonstrated that they can remove bacteria from blood making use of a concept from normal biological process called margination in which leukocytes (white blood cells) adhere to blood vessel walls (see here). Whilst the nitrogenous waste products are much smaller, using fluid flow technology similar to what MIT and NUS have demonstrated may be another way forward.